package cn.ecut.dzy.lock;

/**
 * @program: java-interview
 * @description:Synchronized 和 Lock的区别
 * @author: DingZhenYun
 * @create: 2021-10-25 11:28
 **/

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * 题目：多线程之间按顺序调用，实现A->B->C三个线程启动，要求如下：
 * AA打印5次，BB打印10次，CC打印15次
 * 紧接着
 * AA打印5次，BB打印10次，CC打印15次
 * .....
 * 来10轮
 */
class ShareResource {
    private int number = 1;
    private Lock lock = new ReentrantLock();
    // 这三个相当于备用钥匙
    private Condition condition1 = lock.newCondition();
    private Condition condition2 = lock.newCondition();
    private Condition condition3 = lock.newCondition();

    public void print5() {
        lock.lock();
        try {
            //判断
            while (number!=1){
                condition1.await();
            }
            //干活
            for (int i = 0; i < 5; i++) {
                System.out.println(Thread.currentThread().getName() + "\t " + number + "\t" + i);
            }
            // 唤醒 （干完活后，需要通知B线程执行）
            number = 2;
            condition2.signal();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

    public void print10() {
        lock.lock();
        try {
            //判断
            while (number!=2){
                condition2.await();
            }
            //干活
            for (int i = 0; i < 10; i++) {
                System.out.println(Thread.currentThread().getName() + "\t " + number + "\t" + i);
            }
            // 唤醒 （干完活后，需要通知B线程执行）
            number = 3;
            condition3.signal();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }
    public void print15() {
        lock.lock();
        try {
            //判断
            while (number!=3){
                condition3.await();
            }
            //干活
            for (int i = 0; i < 15; i++) {
                System.out.println(Thread.currentThread().getName() + "\t " + number + "\t" + i);
            }
            // 唤醒 （干完活后，需要通知B线程执行）
            number =1;
            condition1.signal();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }
}

public class SyncAndReentrantLockDemo {
    public static void main(String[] args) {

        ShareResource shareResource = new ShareResource();

        new Thread(() -> {
            for (int i = 0; i < 10; i++) {
                shareResource.print5();
            }
        }, "A").start();

        new Thread(() -> {
            for (int i = 0; i < 10; i++) {
                shareResource.print10();
            }
        }, "B").start();

        new Thread(() -> {
            for (int i = 0; i < 10; i++) {
                shareResource.print15();
            }
        }, "C").start();
    }
}
